8 - Soil

Question 1

Infiltration capacity terms

Answer 1

Infiltration: The flux (flow per unit area) of water passing into the soil.
Infiltration capacity: The maximum flux of water that can pass into the soil at a given time.
Runoff: Excess rainfall that does not infiltrate (net rainfall).

Question 2

Horton results

Answer 2

Results provide cummulative infiltration
If curve below rainfall data = rainfall always less than infiltration capacity therefore no runoff
If rainfall data above curve = runoff from storm event

Question 3

Bucket model/soil results

Answer 3

Field Capacity, 𝑺 = 𝑺𝒎𝒎𝒎
The amount of water held in soil after excess water has drained away and the rate of downward movement has materially decreased.
Permanent wilting point, 𝑺 = 𝟎
This is lower limit of soil water availability to plants, more precisely defined as the state of soil water when plants wilt and do not recover whentheirleavesarekeptinahumid atmosphere overnight
Soil moisture deficit, 𝑺𝒎𝒎𝒎 − 𝑺 extent to which the soil is drier than field capacity e.g. a soil moisture deficit of 50mm implies that 50mm of water are required to return the profile to field capacity